anonymous,
Could you put up a photo of this property and vehicles.
I feel this is a recurring issue at this residence.

The town's office of the Assessor should be informed of any unregistered vehicles. The assessor will investigate the claim by checking DMV documents and by interviewing the home-owners of the surrounding properties to establish a timeline as to how long the unregistered vehicle was/is parked at the residence in question. Complaints can be made anonymously.
Phone: 203-287-7128
Fax: 203-287-7125
Chief Assessor: James W. Clynes
Per Connecticut Statute §14-163, the Commissioner of the Department of Motor Vehicles, on or before the first day of December, annually, furnishes the tax assessors in each town a list containing the names and addresses of the owners of motor vehicles residing in their respective towns, as they appear on the records of the Department of Motor Vehicles, with a description of such vehicles. Vehicles not registered in Hamden but principally garaged or used in the Town of Hamden are considered "located" here.